POS1222 PROGRESSIVE PULMONARY FIBROSIS IN ANTI-SYNTHETASE SYNDROME: A SINGLE CENTER COHORT
Authors: I. Peralta Garcia, A. M. Svensson, A. S. Galindo-Feria, A. Notarnicola, L. Dani, I. E. Lundberg, M. Dastmalchi
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Interstitial lung disease (ILD) is one of the major causes of morbidity and mortality in patients with idiopathic inflammatory myopathies (IIM). <sup>[1]</sup> Within IIM, ILD is frequently found in patients with anti-synthetase syndrome (ASyS). Current treatment is based on a combination of high doses of glucocorticoids and other immunosuppressors such as cyclophosphamide, with progression of ILD despite the treatment. One anti-fibrotic drug, nintedanib, has recently been approved for patients with progressive fibrotic ILD. <h3>Objectives</h3> To explore if within patients with ASyS there is a group with worsening ILD that fits the definition of progressive pulmonary fibrosis (PPF)<sup>[2]</sup> and thus would be eligible for anti-fibrotic treatment.<sup>[3]</sup> <h3>Methods</h3> A single center based retrospective cohort of patients diagnosed with ASyS, ILD involvement, and positivity for specific autoantibodies anti-Jo1, anti-PL7, anti-PL12, anti-EJ and/or anti-OJ (ASyS-AB) was identified using the Swedish Myositis network register. We selected the latest computed tomography (CT) thoracic scans, pulmonary function tests (PFT) and the development of respiratory symptoms according to clinical records. Patients were evaluated based on the INBUILD study criteria<sup>[3]</sup> and the international thoracic and respiratory clinical practice guideline (CPG)<sup>[2]</sup> for the presence of PPF. An experienced thoracic radiologist reviewed the CT scans of those who met the criteria to confirm PPF. <h3>Results</h3> We identified 147 individuals positive for ASyS-AB; 66 of them were not included due to either a follow-up period of less than one year, lack of data in the national registry or absence of ILD. Finally, a cohort of 81 patients was included, 67.9% women, with a median (Q1,Q3) age at disease onset of 58 (48,67) years (Table 1). The median time from disease onset until assessment for PPF criteria was of 6 years. The most prevalent CT finding amongst all groups was fibrotic changes (n=28) neither fitting the usual interstitial pneumonia (UIP) (n=9) nor the fibrotic non-specific interstitial pneumonia (NSIP) (n=6) criteria; followed by inflammatory NSIP (n= 18). 14.8 percent or 19.8 percent (INBUILD and CPG, retrospectively) of the individuals with any type of lung fibrotic pattern on CT met the definition of PPF. <h3>Conclusion</h3> In this cross-sectional study, 15% of patients with ASyS fulfilled the definition of progressive fibrosis and thus could be eligible for anti-fibrotic treatment. To our knowledge, this is the first cohort to demonstrate a possible real-life target of anti-fibrotics in IIM-ILD. <h3>References</h3> [1]Dobloug GC, Svensson J, Lundberg IE, Holmqvist M. Ann Rheum Dis. 2018 Jan;77(1):40-47. [2]Raghu G, Remy-Jardin M, Richeldi L <i>et al.</i>Am J Respir Crit Care Med. 2022 May 1;205(9):e18-e47. [3]Flaherty KR, Wells AU, Cottin V, et al. N Engl J Med. 2019 Oct 31;381(18):1718-1727. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> Irene Peralta Garcia: None declared, Ann Mari Svensson Speakers bureau: Boehringer Ingelheim, Angeles Shunashy Galindo-Feria: None declared, Antonella Notarnicola Speakers bureau: Boehringer Ingelheim, Lara Dani: None declared, Ingrid E. Lundberg Speakers bureau: Boehringer Ingelheim, Maryam Dastmalchi: None declared.